Sun Java Plugin Arbitrary Package Access Vulnerability
   iDEFENSE Security Advisory 11.22.04:

   I. BACKGROUND

   Java Plug-in technology, included as part of the Java 2 Runtime
   Environment, Standard Edition (JRE), establishes a connection between
   popular browsers and the Java platform. This connection enables
   applets
   on Web sites to be run within a browser on the desktop. More
   information
   about Java Plug-in technology is available from
   [14]https://java.sun.com/products/plugin/.

   II. DESCRIPTION

   Remote exploitation of a design vulnerability in Sun Microsystems
   Inc.'s
   Java Plug-in technology allows attackers to bypass the Java sandbox
   and
   all security restrictions imposed within Java Applets.

   A number of private Java packages exist within the Java Virtual
   Machine
   (VM) and are used internally by the VM. Security restrictions prevent
   Applets from accessing these packages. Any attempt to access these
   packages, results in a thrown exception of 'AccessControlException',
   unless the Applet is signed and the user has chosen to trust the
   issuer.

   The problem specifically exists within the access controls of the Java
   to Javascript data exchange in web browsers using Sun's Java Plug-in
   technology. The vulnerability allows Javascript code to load an unsafe
   class which should not normally be possible from a Java Applet.

   III. ANALYSIS

   Successful exploitation allows remote attackers to execute hostile
   Applets that can access, download, upload or execute arbitrary files
   as
   well as access the network. A target user must be running a browser on
   top of a vulnerable Java Virtual Machine to be affected. It is
   possible
   for an attacker to create a cross-platform, cross-browser exploit for
   this vulnerability. Once compromised, an attacker can execute
   arbitrary
   code under the privileges of the user who instantiated the vulnerable
   browser.

   IV. DETECTION

   iDEFENSE has confirmed the existence of this vulnerability in Java 2
   Platform, Standard Edition (J2SE) 1.4.2_01 and 1.4.2_04 from Sun
   Microsystems. It is suspected that earlier versions are vulnerable as
   well. Various browsers such as Internet Explorer, Mozilla and Firefox
   on
   both Windows and Unix platforms can be exploited if they are running a
   vulnerable Java Virtual Machine.

   V. WORKAROUND

   Disabling Java or JavaScript will prevent exploitation as the
   vulnerability relies on the data transfer between the two components.
   Other Java Virtual Machines, such as the Microsoft VM, are available
   and
   can be used as an alternative.

   VI. VENDOR RESPONSE

   This issue has been fixed in J2SE v 1.4.2_06 available at:

      [15]https://java.sun.com/j2se/1.4.2/download.html

   VII. CVE INFORMATION

   The Common Vulnerabilities and Exposures (CVE) project has assigned
   the
   name CAN-2004-1029 to this issue. This is a candidate for inclusion in
   the CVE list ([16]https://cve.mitre.org), which standardizes names for
   security problems.

   VIII. DISCLOSURE TIMELINE

   06/29/2004   Initial vendor notification
   06/30/2004   Initial vendor response
   08/16/2004   iDEFENSE clients notified
   11/22/2004   Public disclosure

   IX. CREDIT

   Jouko Pynnonen (jouko[at]iki.fi) is credited with this discovery.

   Get paid for vulnerability research
   [17]https://www.idefense.com/poi/teams/vcp.jsp

   X. LEGAL NOTICES

   Copyright © 2004 iDEFENSE, Inc.

   Permission is granted for the redistribution of this alert
   electronically. It may not be edited in any way without the express
   written consent of iDEFENSE. If you wish to reprint the whole or any
   part of this alert in any other medium other than electronically,
   please
   email [18]customerservice@idefense.com for permission.

   Disclaimer: The information in the advisory is believed to be accurate
   at the time of publishing based on currently available information.
   Use
   of the information constitutes acceptance for use in an AS IS
   condition.
   There are no warranties with regard to this information. Neither the
   author nor the publisher accepts any liability for any direct,
   indirect,
   or consequential loss or damage arising from use of, or reliance on,
   this information.